Getting from one place to another is what a bridge does. Getting from one kind of fuel to make electricity to another fuel uses a bridge fuel.

That fuel is natural gas. Lots of debate about natural gas as a bridge fuel, too.

Natural gas has been a transitional resource from coal, a high-carbon fuel used to make power. Gas use has increased as coal has decreased. “Coal’s share of U.S. electricity generation between 2000 and 2017 fell from 51% to 30%. Renewables get a lot of credit for this decline, but the truth is that natural gas took most of coal’s market share. Over the past 17 years, the natural gas share of power production doubled from 16% to 32%. Natural gas is now the largest source of power in the U.S.” (Source)

In 2019 the electric power accounted for about 36% of total U.S. natural gas consumption. EIA.

As natural gas replaced coal, that has reduced carbon emissions. Positive. Critics of gas point out that emissions still happen by using natural gas. A concern is that our nation will not leave the bridge. Low cost natural gas may be addictive. That means emissions stay.

Here’s an example of a way gas can find a longer-term place in the power portfolio. National Geographic explains, “New gas-fired ‘flex’ power plants in California, for example, are built to ramp up and down quickly to accommodate shifting supply from wind and solar. Facilities like these bolster the idea that the notion of a ‘bridge’ is misguided; some in the energy and technology industries talk about natural gas as a ‘destination’ fuel that we will need for many years to come.”

In that case natural gas is part of an energy system. Not what some people want.

The luster of cheap natural gas is tarnishing because of emissions. In the US, the Atlantic Coast Pipeline project was halted, for instance. It isn’t just in the US, either:

  • A judge last year decided that an LNG [liquified natural gas] terminal in Gothenburg on Sweden’s west coast shouldn’t be connected to the grid. (Right)
  • Construction on a pipeline between France and Spain was abandoned after regulators on both sides of the border used vetoes to stop it.
  • The Shannon LNG import terminal in Ireland … has been withdrawn as a project to receive incentives from the European Union.
  • The backlash against gas is even burgeoning in Australia, one of the world’s top LNG exporters. (Source)

A Dominion Energy gas plant in Brunswick County, VA

The debate is not just about emissions, but what is at the other end of the bridge – what fuel will be used to make the power we need and have no emissions. Will solar and wind ramp up enough? Nuclear is under pressure but is a massive carbon-free power provider. Hydro power has no carbon. There is always conservation – just don’t require the power in the first place.

We are on the natural gas bridge today, though the view at the end of the bridge is a bit foggy.

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From the Dominion Energy website: How Natural Gas Creates Electricity:

We use a combustion turbine plant to transform the natural gas into electricity.

  1. The combustion of natural gas forces turbine blades to spin.
  2. The spinning turbine is attached to a generator, which produces electricity.
  3. In a combined-cycle plant, exhaust heat is used to create steam. The steam turns an additional turbine and generator to produce more electricity.
  4. Steam is cooled in a condenser by water from a nearby river or lake. The condensed water returns to the plant and the cycle is repeated.